Manipulation of Liquid Metals on a Graphite Surface

Hu, Liang; Wang, Lei; Ding, Yujie; Zhan, Shuie; Liu, Jing

doi:10.1002/adma.201601639

Cited by 149 publications

(135 citation statements)

References 26 publications

Supporting

Mentioning

135

Contrasting

Order By: Relevance

“…In contrast to conventional metals, sp 2 -bonded carbon materials are stable to alloy formation with liquid metals. [25,26] To leverage this property in a platform that is suitable for printed GaLMAs, graphene inks based on cellulose derivatives are used for robust contacts to liquid metal. This class of graphene inks has shown broad process compatibility with excellent electrical conductivity, mechanical durability, and environmental stability.…”

mentioning

confidence: 99%

Wiring up Liquid Metal: Stable and Robust Electrical Contacts Enabled by Printable Graphene Inks

Secor

Cook

Tabor

et al. 2017

Adv Elect Materials

View full text Add to dashboard Cite

electronic materials. By leveraging these unique characteristics, researchers have recently demonstrated advances in reconfigurable, responsive, and stretchable electronic devices. [5][6][7][8] Select applications of liquid metals include soft electronic skins, [9,10] dynamic and flexible antennas, [11][12][13][14] and self-healing and elastic electronics. [15,16] Moreover, the fluid nature of GaLMAs such as eutectic gallium-indium (eGaIn) enables broad process compatibility with additive printing methods such as direct write, inkjet, transfer, and 3D printing. [17][18][19][20][21][22][23] As such, research toward the control and integration of GaLMAs for printed, stretchable, and reconfigurable electronics has attracted broad scientific and practical interest.Despite their promise, the development of liquid metal electronics must overcome several challenges for widespread application. In particular, stable electrical contacts have been identified as a critical challenge for the integration of GaLMAs in electronic circuits and systems. [4] Since gallium alloys rapidly with most metals, GaLMAs lead to unstable or mechanically sensitive interfaces when combined with metal electrodes or interconnects, thereby preventing the reliable integration of eGaIn functionality with conventional electronics. In a recent dramatic demonstration of this effect, Dickey and coworkers exploited the aggressive alloying of eGaIn with silver to direct the motion of liquid metal droplets across a surface, completely removing the silver in the process. [24] Therefore, to enable broader application of eGaIn with conventional circuits, interfacial alloying needs to be suppressed without compromising electrical or mechanical properties.Here, we demonstrate printed graphene as a reliable and high-performance interfacial layer to enable electrical connections to eGaIn. In contrast to conventional metals, sp 2 -bonded carbon materials are stable to alloy formation with liquid metals. [25,26] To leverage this property in a platform that is suitable for printed GaLMAs, graphene inks based on cellulose derivatives are used for robust contacts to liquid metal. This class of graphene inks has shown broad process compatibility with excellent electrical conductivity, mechanical durability, and environmental stability. [27][28][29][30] A thin film (≈100 nm) of fewlayer graphene flakes printed between conventional silver leads and eGaIn acts as a physical barrier, effectively passivating the surface against alloying while retaining the ability to conduct current across the interface. Moreover, graphene interfacial Gallium-based liquid metal alloys (GaLMAs) are a unique class of advanced materials with the potential to offer unprecedented opportunities in stretchable and reconfigurable electronics. Despite their promise, the development of liquid metal electronics must overcome several challenges for widespread application. In particular, stable electrical contacts have been identified as a critical challenge for the integration of GaLMAs in electronic...

show abstract

mentioning

confidence: 99%

Wiring up Liquid Metal: Stable and Robust Electrical Contacts Enabled by Printable Graphene Inks

Secor

Cook

Tabor

et al. 2017

Adv Elect Materials

View full text Add to dashboard Cite

show abstract

“…We selected Carbon/Graphite: these electrodes are highly conductive, show superior resistance to electrochemical erosion/corrosion than metals and are still cost-effective [14]. It is also reported that Graphite helps liquid metal blobs to be wet and stay flat, hence this material appeared as the ideal electrode option for studies -like this one -focused on the shape deformation of liquid metals [13,44].…”

Section: Liquid Metalmentioning

confidence: 99%

Programmable Liquid Matter

Tokuda

Moya

Memoli

et al. 2017

Proceedings of the 2017 ACM International Conference on Interactive Surfaces and Spaces

View full text Add to dashboard Cite

Figure 1. Programmable liquid matter making nonlinear shape of alphabet "S". 7x7 electrodes array dynamic switching to control EGaIn to make an 'S' shape. ABSTRACTIn this paper, we demonstrate a method for the dynamic 2D transformation of liquid matter and present unique organic animations based on spatio-temporally controlled electric fields.In particular, we deploy a droplet of liquid metal (Gallium indium eutectic alloy) in a 7x7 electrode array prototype system, featuring an integrated image tracking system and a simple GUI. Exploiting the strong dependance of EGaIn's surface tension on external electric voltages, we control multiple electrodes dynamically to manipulate the liquid metal into a fine-grained desired shape. Taking advantage of the high conductivity of liquid metals, we introduce a shape changing, reconfigurable smart circuit as an example of unique applications. We discuss system constraints and the overarching challenge of controlling liquid metals in the presence of phenomena such as splitting, self-electrode interference and finger instabilities. Finally, we reflect on the broader vision of this project and discuss our work in the context of the wider scope of programmable materials.

show abstract

“…With outstanding versatile capabilities, liquid metals are opening breakthrough strategies for molding future smart soft robots that had never been anticipated before or hardly achievable by a rigid metal or conventional materials [1,2]. All the evidences collected so far pointed out that, liquid metal machine is evolving via a rather quick way.The latest discoveries on a group of very fundamental phenomena [3][4][5][6][7] of liquid metals further strengthen this endeavor. Unlike former trials on pure liquid metal, the new findings [3][4][5][6] revealed that hybrid structures with both liquid and solid elements together would enable more complicated functions.…”

mentioning

confidence: 99%

“…The latest discoveries on a group of very fundamental phenomena [3][4][5][6][7] of liquid metals further strengthen this endeavor. Unlike former trials on pure liquid metal, the new findings [3][4][5][6] revealed that hybrid structures with both liquid and solid elements together would enable more complicated functions.…”

mentioning

confidence: 99%

“…Reversible behaviors were also achieved via the synthetically chemical-electrical mechanism (SCHEME) [2], which combines chemical dissolution and electrochemical oxidation together. Except for that, facing the big challenge in controlling the shape of liquid metal due to its extremely high surface tension, a latest work [7] opens a way for easily manipulating liquid metal through introducing graphite as special functional substrate. Due to interactions on the interface, liquid metal (LM) in alkaline electrolyte can be fixed into any desired stable shapes like flat, dull and sharp angle.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Liquid metal machine is evolving to soft robotics

Liu

2016

Sci. China Technol. Sci.

Self Cite

View full text Add to dashboard Cite

Making soft robots that can flexibly transform among different morphologies has long been a dream in both science and engineering areas. With outstanding versatile capabilities, liquid metals are opening breakthrough strategies for molding future smart soft robots that had never been anticipated before or hardly achievable by a rigid metal or conventional materials [1,2]. All the evidences collected so far pointed out that, liquid metal machine is evolving via a rather quick way.The latest discoveries on a group of very fundamental phenomena [3][4][5][6][7] of liquid metals further strengthen this endeavor. Unlike former trials on pure liquid metal, the new findings [3][4][5][6] revealed that hybrid structures with both liquid and solid elements together would enable more complicated functions. As it reveals [3], when contacting a copper wire to the liquid metal fueled with aluminum, the wire will be swallowed and then moves back and forth, just like a violin bow. Such oscillating motion could be regulated and speeded up by touching a steel needle on the liquid metal surface. This autonomous oscillator can be developed as a switch element in periodically controlling fluidic, electrical, mechanical and optical functions.In fact, combining solid components with liquid metal can produce more machine roles. For example, contacting nickel particles to sub-millimeter EGaIn droplet in NaOH solution would induce intermittent jumping of the metal droplet [4]. The reason comes from the electron discharge effect due to point contact between liquid metal and solid metal particles in electrolyte. It is the short circuit effect that significantly enhances the near-surface electric field at the particle tips which then causes electric breakdown of the electrolyte and thus drastic hydrogen generation leading to strong propelling force.Alternatively, if intentionally electroplating more other materials like a magnetic Ni layer on the liquid metal, the autonomous Ni/Al/EGaIn machine fueled with aluminum could be manipulated by external magnet or electric field which can realize diverse motion control such as steering, changing direction, start, and stop [5]. Through further coating with soft biomedical hydrogel, the liquid metal motor can even be utilized to deliver drugs.Moreover, liquid metal can be integrated with solid structure to construct various machines. In this side, metal droplet was demonstrated to be used as "wheels" to drive 3D printed vehicle or boat [6]. The hybrid machine thus made adapts to multiple electrolytes especially NaOH solution. Under variable electrical voltages and configurations, the vehicle can be controlled to achieve various progressing, steering, carrying freight and more locomotion states.In earlier efforts, several pivotal findings on shape changeable liquid metal are on the electrically induced liquid metal transformers. It was disclosed that through applying electrical field on the liquid metals immersed in or sprayed with water, very unusual phenomena would occur such as transformation from ...

show abstract

Manipulation of Liquid Metals on a Graphite Surface

Cited by 149 publications

References 26 publications

Wiring up Liquid Metal: Stable and Robust Electrical Contacts Enabled by Printable Graphene Inks

Wiring up Liquid Metal: Stable and Robust Electrical Contacts Enabled by Printable Graphene Inks

Programmable Liquid Matter

Liquid metal machine is evolving to soft robotics

Contact Info

Product

Resources

About